Floor strip

ABSTRACT

A thin decorative thermosetting laminate of postforming quality is glued to a longitudinal carrier to form a floor strip. The laminate has a thermosetting resin as well as hard particles impregnated therein to increase the abrasion resistance of the laminate. The carrier generally has a cross section of a dilatation, transition or a finishing profile, depending on the intended use of the floor strip. The floor strip has a tab portion on a surface that engages a channel on a floor tile or a reducer. The tab portion locks the floor strip into place and prevents movement of the floor tile or the reducer with respect to the floor strip.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. Ser. No. 08/817,391,filed Apr. 25, 1997 now U.S. Pat. No. 6,517,935 and acontinuation-in-part of U.S. Ser. No. 09/986,414, filed Nov. 8, 2001 nowabandoned, the entire disclosures of which are hereby incorporated byreference.

BACKGROUND OF INVENTION

1. Field of the Invention

The present invention relates to a process for the production of a floorstrip such as a dilatation profile, a transition profile or a finishingprofile. The present invention also relates to the features of the floorstrip.

2. Description of the Related Art

It is previously known to produce floor strips such as metal strips,wood veneer coated strips and strips of homogeneous wood. However, suchfloor strips generally do not adequately match the pattern of the otherportions of the floor. Thus, there is a strong desire to bring about afloor strip with the same pattern as on a floor of thermosettinglaminate. During the last few years these floors have become very usual.For instance they are made with a wood pattern, marble pattern and fancypattern. Possibly you can use a homogeneous wood strip or a woodveneer-coated strip for a few of the wood patterned floors. Previouslyknown strips do not go well together with all the other floor patterns.

These floor strips are provided in a floor system in order to provide atransition or edge to the floor, such as at the corner of the wall orbetween rooms. They may also be provided between rooms having differenttypes of flooring, such as carpet and tile, or different heights ortextures of tiles. However, conventional floor strips do not adequatelyprovide a transition between differing floor types because they cannotadequately cover the gap between the differing floor coverings or thediffering heights of the tiles.

However, it also a problem for sellers of floor strips to inventorydiffering types of transition profiles, especially in a pattern or colorto match a single floor. Thus, there exists a need to provide a singlefloor strip which can satisfy a number of differing requirements, such abeing useful as a finishing profile, a dilatation profile, and atransition profile.

SUMMARY OF INVENTION

The purpose of the present invention is to provide a floor strip withimproved abrasion resistance and features to overcome the problems inthe art.

According to the present invention it has quite surprisingly beenpossible to meet the above needs and bring about a process for theproduction of floor strips such as a dilatation profile, a transitionprofile or a finishing profile. The process comprises glueing,preferably under heat and pressure a thin decorative thermosettinglaminate of post-forming quality having an abrasion resistance measuredas IP-value>3000 revolutions, preferably >6000 revolutions, on alongitudinal carrier, which carrier preferably consists of a fibre boardor a particle board with a rectangular cross-section and at least twoopposite rounded-off edges.

The post-forming laminate is glued in one piece on the upper side andtwo long sides of the carrier via the rounded-off edges, whereupon oneor more floor profiles having the same or different cross-section ismachined from the laminate coated carrier. According to anotherembodiment the carrier can be provided with a rectangular cross-sectionwith three rounded-off edges.

From the same body, the laminate clad carrier, several profiles withvarying shape can be machined. Usually a milling machine is used formachining the different kinds of profiles from the laminate coatedcarrier. The carrier may also be molded to achieve various profileswhich may be required. Additionally, the carrier is preferably waterresistant or even waterproof. In a preferred embodiment the carrierconsists of a high density fibre board made of fine fibres, such asknown in the industry as medium density fiberboard (MDF) or high densityfiberboard (HDF).

Advantageously, a heat and moisture resistant glue is used at theglueing. Preferably the glueing is carried out under heat and pressure.For instance, the pressure can be regulated by means of rollers whichpress the laminate against the carrier. The temperature can, forinstance, be regulated with heating nozzles which can give an evencurrent of warm air.

Suitably the post-forming laminate consists of at least onemonochromatic or patterned paper sheet impregnated with a thermosettingresin, preferably melamine-formaldehyde resin and preferably one or moresheets for instance of parchment, vulcanized fibres or glass fibres. Thelast mentioned sheets are preferably not impregnated with anythermosetting resin, but the thermosetting resin from the sheetssituated above will enter these sheets at the laminating step, where allsheets are bonded together. Alternatively, the sheet can be a metallicfoil or a layer of paint.

Generally the term post-forming laminate means a laminate which is soflexible that it can be formed at least to a certain extent after theproduction thereof. Ordinary qualities of thermosetting decorativelaminates are rather brittle and cannot be regarded as post-forminglaminates.

Usually the post-forming laminate includes at least one uppermosttransparent paper sheet made of α-cellulose and impregnated with athermosetting resin, preferably melamine-formaldehyde resin. Thisso-called overlay is intended to protect an underlying decor sheet fromabrasion.

Often at least one of the paper sheets of the postforming laminateimpregnated with thermosetting resin, preferably the uppermost one, iscoated with hard particles, e.g., those having a Moh's hardness of atleast 6, preferably between 6 and 10, similar to the Moh's hardness ofat least silica, aluminium oxide, diamond and/or silicon carbide. Thehard particles have an average particle size of about 1-80 μm,preferably about 5-60 μm evenly distributed over the surface of thepaper sheet. In a preferred embodiment the hard particles are applied onthe resin impregnated paper surface before the resin has been dried. Thehard particles improve the abrasion resistance of the laminate. Hardparticles are used in the same way at the production of laminates whichare subject to a hard wear such as flooring laminates.

The abrasion resistance of the post-forming laminates is testedaccording to the European standard EN 438-2/6: 1991. According to thisstandard the abrasion of the decor sheet of the finished laminate to theso-called IP-point (initial point) is measured, where the startingabrasion takes place. The IP-value suitably lies within the interval3000-20000, preferably 3000-10000 revolutions. Thus, the manufacturingprocess according to the invention makes it possible to produce laminateclad profiles with the same surface pattern and about the same abrasionresistance as the laminate floorings they are intended to be usedtogether with.

The carriers for the floor strips to which the post-forming laminate isglued can be made of differing profiles to accommodate the specificcircumstance, namely whether a dilatation, transition or finishingprofile is required. The profile, for example a dilatation profile,comprises a general T-shape whereby a first plane extending verticallyalong the length of the floor strip intersects about in the middle of asecond horizontally oriented plane. A profile removes about half of thesecond plane to form a rotated upside down L-shape, which is usedadjacent a wall or on a stepped surface. A dilatation profile is similarto a finishing profile, but the second plane is oriented off ofhorizontal or it is divided into two planes, one at a different levelthan the other, or one side is removed altogether, which provides asmoother transition between uneven tiles, a carpet and tile, ordiffering tile textures. The pattern of the profiles can also be adaptedto other flooring materials than laminate floorings, such as parquettefloorings and soft plastic floorings.

In order to overcome the problems associated with transitioning betweencarpet and tile, differing textures of tiles or differing heights oftiles, the second plane may have a tab portion on its tile/carpetengaging surface depending orthogonally away from the second plane anddisplaced away from the first plane. The tab is used to engage a reducerthat extends between the floor surface and the engagement surface of thesecond plane. The reducer is configured to maintain a horizontalorientation of the second plane and provide a smoother transitionbetween the tile surfaces in the finishing, transition or dilatationprofile when they are used between uneven tile surfaces, differing tiletextures or between carpet and tile. The tab portion fits into a grooveon the upper surface of the reducer in mating fashion to create a solidlock between them.

Alternatively, the tab portion may be engaged into the edge of a tilepanel on the floor. In this situation, the tiles adjacent to thetransition area may require a groove cut into them near the transition.Such allows the tab portion to maintain a firm and locked relationshipwith the tile surface and provide a better transition between the tilesurface and the respective profile. Further, a tab portion may beprovided on both sides of the second plane respective to the first planeto further smooth the transition area between the first tile surface,the floor strip and the second surface.

The design of the tab may come in varying styles, there may be astraight block type tab, a t-nut type, various interlocking styles and achannel type arrangement. Such types depend on the particularrequirements of the tiling circumstance.

This inventive floor strip according to the above may be used as atransition piece between various tongue and groove panels to provide asmooth and aesthetic transition between floor sections having dissimilarsurfaces, such as those between a carpeted area and a tiled area, a thintile area and a hardwood floor, two tile areas having differingtextures, etc.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be explained further in connection with theembodiment example below and the enclosed figures of which:

FIG. 1 illustrates a post-forming laminate glued to a longitudinalcarrier,

FIG. 2 illustrates a dilatation profile with a post-forming laminateglued thereto,

FIG. 3 illustrates a finishing profile with a post-forming laminateglued thereto,

FIG. 4 illustrates a transition profile with a post-forming laminateglued thereto,

FIG. 5 illustrates an exploded view of a dilatation profile extendingbetween uneven tile surfaces,

FIGS. 6A-6C illustrate an assembled view of a locking tab/reducerassembly,

FIGS. 7A-7C illustrate an assembled view of a non-locking tab/reducerassembly,

FIG. 8 illustrates an assembled view of a dilatation profile having twotab portions locking with edge panels,

FIG. 9 shows a perspective view of the invention according to oneembodiment of the invention,

FIGS. 10-14 illustrate tab designs according to other embodiments of theinvention.

DETAILED DESCRIPTION OF THE INVENTION

In the figures of illustrating a floor strip 100, the thickness of thepost-forming laminate 1 has been magnified as compared to the size ofthe carrier 2 and the profiles, e.g. 3-5 respectively, to betterillustrate that a post-forming laminate 1 is glued to the carrier 2 andthe profiles 3-5 respectively. Of course the FIGS. 1-4 only show oneembodiment of the carrier 2 and the profiles 3-5 respectively which canbe produced according to the invention. Various other designs arepossible as shown in the other drawing figures.

For example in one embodiment, a roll of transparent so-called overlaypaper of α-cellulose with a surface weight of 25 g/m² is impregnatedwith an aqueous solution of melamine-formaldehyde resin to a resincontent of 70 percent by weight calculated on dry impregnated paper.Immediately after the impregnation, aluminium oxide particles with anaverage particle size of 50 μm are applied to the upper side of thepaper in an amount of 7 g/m² by means of a doctor-roll placed above thepaper web. Thus, the hard aluminium oxide particles are then applied tothe still-wet melamine-formaldehyde resin which has not dried.

The impregnated paper web is then fed continuously into a heating oven,where the solvent in the resin evaporates. Simultaneously, the resin ispartially cured to so-called B-stage. Thereby the aluminium oxideparticles are enclosed in the resin layer and accordingly concentratedto the surface of the product obtained which is usually called aprepreg. The prepreg web obtained is then rolled again.

A roll of conventional non-transparent decor paper with a decor patternprinted thereon and having a surface weight of 80 g/m² is treated in thesame way as the overlay paper except for the fact that no aluminiumoxide particles are applied and that the resin content was 50 percent byweight calculated on dry impregnated paper.

A roll of unimpregnated parchment with a surface weight of 120 g/m² isused at the production of the post-forming laminate.

The two prepreg webs impregnated with melamine-formaldehyde resin andthe unimpregnated parchment web are then pressed between two press bandsof a continuous laminating press to a decorative post-forming laminate.At the pressing, a prepreg web of α-cellulose is placed on top with theside with the hard particles directed upwards. Underneath follows aprepreg web of decor paper and at the bottom a web of parchment. Theprepreg webs and the parchment web are pressed together at a pressure of35 kp/cm² and at a temperature of 170° C. The decorative post-forminglaminate obtained is then cut with roller knives to strips of suitablelength and width.

A longitudinal carrier 2 with a rectangular cross-section and twoopposite rounded-off edges according to FIG. 1 are machined from a fibreboard or other substrate material by means of a milling machine. Thefibre board is a water resistant board of so-called MDF-quality (mediumdensity fibre board quality) or, alternatively, HDF quality (highdensity fibre board quality), made of finely divided fibres with anadhesive to bond the fibres together.

A strip of post-forming laminate 1 is now glued under heat and pressureto the longitudinal carrier 2 with a heat and moisture resistant glue.The pressure is regulated with rolls which press the laminate againstthe carrier and the temperature 1 is regulated with heating nozzleswhich blow an even current of warm air.

Following the above process, the abrasion resistance of the post-forminglaminate obtained was measured. Then a value for the IP-point amountingto 7000 revolutions was obtained.

The different structures and designs of the profiles for floor strip100, namely the dilatation, finishing and transition will now bedescribed with respect to FIGS. 2-9. A dilation profile 3 according toFIG. 2 can be machined from the laminate clad carrier by milling. Twofinishing profiles 4 according to FIG. 3 or one transition profile 5according to FIG. 4 can be produced from the same carrier. This resultsin a rational and cost-saving production. Alternatively, the carrierscan be the shape as shown in FIGS. 2-9 before the post-forming of thelaminate is commenced.

FIG. 5 shows an exploded view of one of the preferred embodiments of theinvention, wherein floor strip 100 is attached between two differingsets of tiles, thin tile 70 and thicker tongue and groove tiles 80 and81 (shown in mating relationship), all on a subfloor 500. FIG. 6A showsthe components of FIG. 5 assembled together. In these figures, floorstrip 100 is a dilatation profile having a T-shape, with a first plane50 arranged vertically in use and a second plane 60 orientedhorizontally and connecting to the first plane along its mid-sectionforming a “T.” The second plane overhangs the first plane on a firstside 61 and a second side 62. A tab 180 extends from the bottom plane offirst side 61 of the second plane.

Due to the differing heights of the tiles 70 and 80/81, a reducer 90will be required to provide a smooth transition. Reducer 90 has a heightcorresponding to the height difference between the tiles and also has agroove 91 on its upper surface for acceptance, in a locking manner, oftab 180. Upon assembly of tiles 70, 80 and 81 and floor strip 100, thetab fits into groove 91 and then the reducer is assembled in matingposition between an edge 71 of tile 70 and the first side 61 of thesecond plane. The design of the tab and reducer prevents the reducerfrom laterally moving in relation to floor strip 100 in an assembledcondition. Although a simple tongue and groove design is shown, otherengagement means may be used (See FIGS. 9A-9F, discussed below) whichhave locking designs which lock the floor strip and reducer together. Ateach of these mating portions, glue may be used to additionally securethe components together. The reducers 90 (as well as the reducers of thesubsequent described embodiments) may carry on an exposed outer surfacea pot forming laminate (not shown) in a manner similar to that shown inFIGS. 1-4.

Reducer 90 may have alternate designs, which are illustrated in FIGS. 6Band 6C. Reducer 90, shown in FIGS. 5, 6A and 6B, has a sloped portion93, which provides a more gradual transition between a tiled floorsection having a higher height than an adjacent floor tile section. Onthe other hand, Reducer 95, shown in FIG. 6C, has a vertical side 96,which would provide more of a small step between the different tilefloor sections.

Another embodiment of the invention is shown in FIGS. 7A-7C, wherebyinstead of tab 180 locking into a reducer, it provides a back stop for areducer 97 which does not have any groove. Other aspects of thisembodiment are congruent to those of the previous embodiment and willnot be repeated herein.

Reducer 97 is more or less a rectangular box design having one slopedside 109 which as in the previous embodiment provides a gradualtransition between floor heights. Reducer 97 does not have a groove,rather the back side 99 is abutted against tab 180 when floor strip 100and reducer 97 are in their assembled positions, as shown in FIG. 7A. Aglue or other adhesive may be used to maintain the parts in theirpositions and prevent reducer 97 from laterally moving in relation tofloor strip 100. Alternatively, reducer 98 may be used in place ofreducer 97. Reducer 98 has a rectangular box shape which provides a stepbetween floor heights rather than in a sloped fashion.

A further embodiment of the invention is shown in FIG. 8. In thisembodiment, floor strip 100 is used between two adjacent floor tilesections having similar heights. Further, both first side 61 and secondside 62 of the second plane 60 have tabs 180 and 181, respectively.Tiles 200 and 210 have grooves 201 and 211 respectively. Tabs 180 and181 fit into grooves 201 and 211 by a tongue and groove style, however,other engagement styles may be used (See FIGS. 9A-9F below) which eitherpositively lock the parts together or simple provide a guide forassembly. Such a design does not require the use of a reducer betweenthe tile and the floor strip.

The tab and reducer groove need not be a simple tongue and groovedesign, as outlined in FIGS. 5-8. These were described merely by way ofexample using floor strip 100 with tab portion 180 as shown in FIG. 9.Alternatives of the tab on the floor strip in conjunction with a reducerare shown in FIGS. 10-14. Additionally, the reducers described inconjunction with the invention as a spacer between uneven floor tiles isnot necessary. Should the tiles have similar height, a reducer may beremoved and such slots which are described in the reducer may also becut into the appropriate floor tile for positive locking or preventionof associated movement.

In FIG. 10A, a tab 1800 on floor strip 101 has the shape of a t-nut. Anassociated reducer 1000 has a shape similar to the t-nut cut through itslongitudinal length thereof. Tab 1800 fits into the reducer 1000 bysliding the tab into an end portion of the reducer and along the lengthof the reducer. Such a design allows for a positive locking in a lateraldirection while allowing movement along the longitudinal axis of thefloor strip.

The designs of the tab portion as shown in FIGS. 11A, 12A and 14A show atab portion that snaps into the associated reducer. In FIG. 11A, a tab1800 of floor strip 102 has a pair of upwardly facing angled teeth 1850and 1851. A reducer 1100 used in association with tab 1800 has a slot1105 cut there through having an opening congruent to the design of thetab. When tab 1800 and reducer 1100 are assembled together, floor strip102 is placed atop the reducer. Upon sufficient pressure on the floorstrip, tabs 1801 will snap into the slot 1105. Teeth 1850 and 1851prevent tab 1801 from being removed from slot 1105 of reducer 1100providing a positive locking together.

Tabs 1802, 1820 and 1803 shown in FIGS. 12A and 14A, have a similardesign for the upwardly facing teeth as shown in FIG. 11A, but have adiffering number of teeth. Similarly, reducers 1200 and 1400, used inassociation with these tabs respectively, also have slots 1205 and 1405which are congruent to the associated tabs. A tile 1225 also has a slotnear its edge for acceptance of the tab 1820. Each slot design allowsfor the tab portion to be snapped into the associated slot for apositive locking between the tab and the slot. Although the slot drawnin these figures has a shape congruent to the shape of the associatedtab, such is not required. The slot must only be of sufficient designwhereby the tab can snap into the slot and whereby the design of theslot prevents removal of the tab. FIG. 12B also shows a floor strip 103having a pair of tabs whereby the tabs snap into both a reducer and theassociated tile. However, such a specific case is not required. Floorstrip 103 may be snapped into a pair of tiles or a pair of reducers.

In FIG. 13A, floor strip 104 has a pair of spaced tabs 1380 and 1381having a generally triangular profile and extending along the length ofthe floor strip. Tabs 1380 and 1381 provide a channel by which reducer1300 is held between the tabs under floor strip 104. Such a designprevents lateral movement of reducer 1300 in relation to floor strip104.

Although the present invention has been described and illustrated indetail, such explanation is to be clearly understood that the same is byway of illustration and example only, and is not to be taken by way oflimitation. Other modifications of the above examples may be made bythose having ordinary skill which remain within the scope of theinvention. For instance, the examples are described with reference to adilatation profile for the carrier of the floor strip. However, such taband reducer designs work just as well with a finishing profile as wellas a transition profile, and whether used on carpet or floor tiles.

1. A floor strip assembly to cover a gap between a first and secondfloor surface, comprising a longitudinal carrier comprising a ribextending along a longitudinal axis thereof, a plane extendingorthogonal to the rib having an engaging surface and an upper surface,and a tab portion on the engaging surface extending away from theengaging surface, and a thermosetting laminate comprising hard particleswhich impart abrasion resistance to the laminate, wherein the laminateis glued onto the upper surface, an upper end of the rib attaches to theplane along a central axis thereof to form substantially a T-shapeprofile for the floor strip, dividing the plane into a first side and asecond side, the tab portion is located on the first side engagingsurface of the plane and a second tab portion is located on the secondside engaging surface of the plane and extends orthogonal therefrom, andat least one of the first and second tab portions engages a channel inone of the first and second floor surfaces.
 2. The floor strip assemblyaccording to claim 1, further comprising a reducer having an upper sidethat engages the engaging surface and a channel within the upper sidethat engages the tab portion.
 3. The floor strip assembly according toclaim 2, wherein the reducer is assembled between the first floorsurface and the engaging surface and is configured to keep the plane ina horizontal orientation when the first and second floor surfaces havedifferent thicknesses.
 4. The floor strip assembly according to claim 2,wherein the tab portion slidingly engages the channel when the reducerengages the engaging surface.
 5. The floor strip assembly according toclaim 2, wherein the tab portion snap-fits into the channel.
 6. Thefloor strip assembly according to claim 1, wherein the tab portion isone of a general hook shape, and a lip is formed at a point of the hook,and a generally bulbous shape having a plurality of vertically spaced,upwardly facing teeth.
 7. The floor strip assembly according to claim 1,further comprising a reducer having an upper side that engages theengaging surface and an inner side that abuts the tab portion to preventlateral movement thereof.
 8. The floor assembly according to claim 7,wherein the tab portion is one of a generally rectangular shape abuttingthe inner side of the reducer, and a pair of extensions, which abut anouter and the inner side, respectively, of the reducer.
 9. The floorstrip assembly according to claim 1, wherein the tab portion engages achannel in the first floor surface.
 10. The floor strip assemblyaccording to claim 1, wherein the upper surface comprises a generallyplanar surface with two opposite rounded-off edges.
 11. The floor stripassembly according to claim 10, wherein the laminate coverssubstantially the entire planar surface and along the rounded-off edges.12. The floor strip assembly according to claim 1, wherein the carrieris water resistant.
 13. The floor strip assembly according to claim 1,wherein the laminate comprises at least one patterned paper impregnatedwith a thermosetting resin.
 14. The floor strip assembly according toclaim 13, wherein the thermosetting resin is melamine-formaldehyde. 15.The floor strip assembly according to claim 13, wherein the laminatefurther comprises one or more sheets consisting of fibers selected fromparchment, vulcanized or glass fibers which are not impregnated with athermosetting resin.
 16. The floor strip assembly according to claim 1,wherein an upper most sheet of the laminate is coated with hardparticles selected from the group consisting of silica, aluminum oxide,silicon carbide and combinations thereof, the hard particles having anaverage size of 1-80 μ.
 17. The floor strip assembly according to claim1, wherein the laminate comprises at least one transparent overlay ofα-cellulose impregnated with a thermosetting resin.
 18. The floor stripassembly according to claim 17, wherein the overlay is impregnated withmelamine-formaldehyde resin.